It occurred to me that I could compile templates written using general program mode into python. Doing this could lead to template execution speed improvements of anywhere from 10 to 50 times. (GPM templates begin with the word "program:".) Building the GPM compiler would be a fair amount of work, so it is worth the effort only if people actually use GPM.

Column coloring uses GPM, but as these templates are invoked only for the books shown on the library view, the payback is not nearly as large as one would get when compiling a template for a composite custom column.

Could anyone who uses GPM in a custom column post here? If you post, it would be nice to get an idea of the complexity of the program. I don't care what it does, only how many function calls it makes. Example programs would be nice, if you are willing to share them.